Peripheral component interconnect-express (PCIe) draws increasing attention because of its high data transmission rate, for example, a highest rate of PCIe 16X 2.0 can reach 10 gigabyte per second (GB/s). However, a transmission distance of PCIe is relatively short, and a typical transmission distance is 15 to 30 centimeter (cm), which limits an application scope of a PCIe device. Currently, extended transmission of PCIe data can be implemented through the Ethernet, increasing the transmission distance of PCIe, thereby expanding an application scope of a PCIe device.
In the prior art, when PCIe data is transmitted through the Ethernet, there is a technical problem that a uniform back pressure is generated in an entire data transmission link if any endpoint device generates back pressure.